Reflective road marker



April 16, 1968 E. H. KONE 3,377,930

REFLECTIVE ROAD MARKER Filed Maron 1, 196s INVENTOR United States Patent O 3,377,930 REFLECTIVE ROAD MARKER Elliott H. Kone, Thimble Farms,

Branford, Conn. 06405 Filed Mar. 1, 1966, Ser. No. 530,903 4 Claims. (Cl. 94-1.5)

ABSTRACT OF THE DISCLOSURE The disclosure deals with a road marker having a base cup and a resilient diaphragm secured thereto at the top to seal the cupf-rom the outside, with the diaphragm carrying on a central portion an external traffic lane i11- dicator land being over its remaining portion at least in part molded int-o a depression of substantial U-section and extending continuously around the central diaphragm portion.

This invention relates to road markers in general, and to road markers of light-reflective type in particular.

Reflective road markers along designated traflic lanes are highly desirable and preferable to the usual painted traffic lines on most roads, not only because such markers have at even fairly wide spacing a similar effect on a driver in daylight as have painted traffic lines and they act like unmistakable light beacons in the dark and are clearly visible over a considerably greater distance than the usual white or yellow trafllc lines, but also because they will function properly in many instances where traffic lines are recognized by a driver only with diiculty, or not at all, as on wet or foggy roads, or on newly snow-plowed roads, or in the light glare from oncoming automobiles, for example. Yet, even though quite a few reflective road ma-rkers are known they are virtually nonexistent on roads, the reason therefor being that they were foundy to be all too readily damaged or destroyed by fast-moving automotive vehicles running over them occasionally, but especially by heavy blades of snowplowing vehicles which necessarily have to pass over them. Among the prior road markers which under these and other traflic conditions stood up longer on the average than others are those having a reflector system mounted on a resilient diaphragm in a road-embedded base in which it has freedom to yield under a passing vehicle wheel or snow-plowing blade. Still while these road markers have in these characteristics apparently the most promising remedies yet devised to cope with traffic conditions, a few among many will nevertheless fail at times under more severe trafllc conditions, wherefore the reliability of their guide and safety performance is not of that desired and even required high standard which would make their periodic inspection virtually unnecessary and involve at the most only negligible repair and maintenance cost for an installation of major proportions. Thus, while even on severe yield action of such road markers to thereover passing vehicles, including snow plowers, their diaphragms -would for the longest time safely withstand the ensuing resilient lexure, their also ensuing resilient stretch, being even largely one-sided on impact, will be particularly severe and may even torture the diaphragm elastomer on yielding to a vehicle passing thereover at abusive speed. Further, the severe stretch response of such a diaphragm to operational yield lends fairly sharp blow characteristics to the impact from a high-speed vehicle on the diaphragm and, hence, also on the reflector system thereon which may well damage the latter. The severity of the stretch response of such a diaphragm to its yield action is even aggravated by the air therebeneath which on the brief impact of a passing ICC vehicle with the marker responds like an entrapped air mass owing to the required sealed diaphragm closure of the road-embedded marker base to keep out foreign matter. It is thus the resilient stretch response of these diaphragms in yielding action which is the obstacle in achieving in road markers the aforementioned high standard of reliability in their guide and safety performance. l lt is the primary aim and object of the present invention to provide a reflective road marker which in its guide and safety performances is of the aforementioned high standard, by resorting to a diaphragm mount of the reflector system which in its operational yield to a vehicle passing thereover is either not stretched, or is stretched only negligibly and incomparably less than prior diaphragms, thereby to overcome the obstacle for achieving this high standard of reliable performance of the pn'or markers.

It is another object of the present invention to provide a reflective road marker of this type of which the diaphragm is flexible, and as a primary feature is in normal functioning disposition of sufficiently large area that it will on operational yield undergo its entire deformation by mere flcxure and virtually without tension.

It is a further object of the present invention to provide a reflective road marker of this type of which the aforementioned flexible diaphragm is preformed, preferably by molding, to a predetermined section and is also resilient so that it will substantially keep its shape in relaxed condition, with the aforementioned large area of the diaphragm being provided by preforming the latter to the requisite extent in deviation from a planar section, whereby the diaphragm will have recovery power for selfrestoration to its normal functioning disposition after each opeartional yield. Also, with the diaphragm acting, on operational yield, largely in flexure and without any significant stretching, its impact with a vehicle wheel passing thereover even at high speed is fairly soft and far from inducing shock that might damage the reflective system.

Another object of the present invention is to provide a reflective road marker of this type in which the air in the diaphragm-sealed marker base will not only not impede operational yielding of the diaphragm and thus be without any stress effect on the latter, but will on operational yield even assist in compelling such deformation of the diaphragm as will lend it optimum recovery force for self-restoration to its normal functioning disposition. To this end, the aforementioned preformed diaphragm is of such section that its deformation on operational yield proceeds in a fashion at which ensuing local reduction of the volume of the diaphragm-sealed marker base compels other local increase of this volume to a more or less compensatory extent with the aid of the locally displaced air in the marker base which, however, undergoes no appreciable compression in the process.

A further object of the present invention is to provide a reflective road marker of this type of which the diaphragm is preferably springbacked for its restoration after operational yield to normal functioning disposition with even greater vigor and sufficient snap to throw off precipitation, applied skidpreventing sand or any other matter which might interfere with proper functioning of the marker in point of light reflection or operational yield, or both. With this arrangement, the backing spring may be arranged to perform as contemplated without being under appreciable load and thus being virtually non-dellected in normal functioning disposition of the diaphragm, so that the spring is not subject to tiring. Even more important, in using a backing spring the elastomer of the diaphragm may be kept at rather small thickness at which it is highly flexible without undergoing any appreciable internal stresses with ensuing long life of the diaphragm.

Still another object of the present invention is to provide a reflective road marker of this type of which the aforementioned spring-backed resilient diaphragm is of such section that on operational yield thereof the same will be flexed in the manner of a snap-over spring, with the snap-over of the diaphragm occurring virtually on impact with a passing vehicle wheel and in snap-away fashion from the latter. In thus arranging for snap-over of the diaphragm in its operational yield, its yield response in mere harmless flexure is even further enhanced assuredly to the exclusion of any potentially harmful stretch or tensile stresses, and the same will on and by virture of snap-over also emits a sound which is clearly heard by the offending driver and which is quite similar to the alarmingy sound of a moving deflated tire and, hence, serves as an unmistakable warning to steer clear of these road markers.

Further objects and advantages will appear to those skilled in the art from the following, considered in conjunction with the accompanying drawings.

In the accompanying drawings, in which certain modes of carrying out the present invention are shown for illustrative purposes:

FIG. l is a plan view of an installed road marker embodying the present invention;

FIG. 2 is an enlarged section through this road marker as taken substantially on the line 2-2 of FIG. 1;

FIG. 3 is a fragmentary' section through the same road marker in a different operating condition; and

FIG. 4 is another fragmentary section through the road marker in another different operating condition.

Referring to the drawings, and more particularly to FIGS. 1 and 2 thereof, the reference numeral 10 designates a road marker having a base 12 and a diaphragmmounted trafiic lane indicator 14 which is preferably of light-reflective type. The base 12 is in the general form of a cup having a bottom i6 and an upright rim 18 dening a chamber 2@ which is open at the top of the rim, with the base 12 being in suitable manner embedded in a road R so as to be substantially ush therewith at the top of its rim (FIG. 2).

The flexible diaphragm 22 of the traic lane indicator 14 is circumferentially anchored to the base rim 1S intermediate its top and bottom, with the remainder of the diaphragm extending across this rim to seal a part 24 of the chamber 26 from the outside. The reflective lane indicator T d is arranged on top of the diaphragm 22 on a preferably central portion thereof, and suitable spring means 26 is provided in the interior of the sealed chamber 24 yieldingly to hold the diaphragm 22 in a normal functioning disposition (FiG. 2) in which the lane indicator 14 projects above the top of the base rim 18. As fully explained hereinafter, the diaphragm 22 and lane indicator 14 thereon will, on the passage of a vehicle wheel or snow-plowing blade thereover, yield into the base 12 and thereafter return to normal disposition (FIG. 2).

In a typical road installation, road markers of this type are installed at spaced intervals along an imaginary line which, for example, divides the road into traffic lanes for travel in opposite directions. The drivers of vehicles travelling on the road will in daylight readily perceive the lane indicators of the markers as they approach them and thus be guided along the proper lanes, and drivers will be guided as safely along proper lanes in the dark by the reliected light of the headlights of their Vehicles at the indicators of road markers ahead. If perchance a driver should carelessly or under any other circumstances steer his or her vehicle over an installed road marker, the diaphragm-mounted lane indicator thereof will operationally yield suiiciently into the marker base to present no obstacle to the thereover passing wheel and remain undamaged, with the diaphragm-mounted lane indicator being urged back into its normal functional disposition (FIG. 2) with the passage of the wheel. Markers of this type may also be road-installed for other purposes, such as indicating both sides of traic lanes, traffic lanes at parting roads, Crossovers from one lane to another, and runways on airfields, for example.

For its anchorage to the marker base 12, the diaphragm 22 is with an outer peripheral margin 28 thereof clamped between superposed sections 30 and 32 of the base rim 18 of which section 30 is the rim proper of the base 12 and section 32 is a clamping ring secured to a top flange 34 on the base 12 as by screws 35.

The lane indicator 14 comprises in this instance a lightreliective lens 36 of any suitable, preferably plastic, kind which is inserted inra holder 3S of any. suitable material, preferably durable plastic. The holder 3S, which has opposite windows 40 foi exposing the lens 36 to the View of oncoming drivers as well as to the light from the headlights of their vehicles, is secured to the top of the diaphragm 22 and preferably to a central portion 42 thereof. To this end, a screw 44 on the inside of the diaphragm 22 passes through an opening i6 in the latter and is threadedly received in a post formation 4S of the lens holder 3S. For additional arrest of the lens holder 38 against turning movement on the diaphragm 22, the same is with its opposite sides 50 received between spaced rib formations 52 on the diaphragm 22.

In accordance with an important aspect of the present invention, the diaphragm mount of the lane indicator is arranged so that it will, on operational yield into the marker base under a vehicle wheel or snow-plowing biade passing thereover, act in exure and without appreciable tensile stresses. To this end, the diaphragm 22 is of any suitable flexible material, and as a primary feature is over its exposed extent inside the clamped peripheral margin 28 thereof of an area which is larger than the cross-sectional area of the sealed chamber 24 suciently to have in its normal functioning disposition (FIG. 2) adequate slack to act in flexure without any appreciable tension on its operational yield deformation. Thus, with the spring means 26 in the sealed chamber 24 bearing, through intermediation of a diaphragm-backing disc 56, at least against the central diaphragm por-tion 42 on which the lane indicator 14 is mounted, it would be entirely feasible to make the diaphragm 22 of any suitable sheet material which merely needs to be exible so as to slacken in a manner like or similar to the loop-like diaphragm section 60 in FIG. 2. It is preferred, however, to mold the diaphragm from any sui-table tough elastomer, such as, for example, neoprene sheet with its known resistance properties to all kinds of weather, temperatures and chemicals to which it will be subjected in an installed road marker. The diaphragm 22 is preferably molded in a sectional shape which may be quite similar to that shown in FIG. 2, and substantially keeps its molded shape when relaxed.

The spring means 26 is in the preferred form of a conical helical compression spring which in normal functional disposition of the diaphragm 22 (FIG. 2) is virtually relaxed, being then under the negligible load of the non-stressed light-weight diaphragm and also light-weight lane indicator thereon as well as light-weight diaphragmbacking dise 56. As shown, the spring 26 rests with its narrow endon the base bottom 16 and with its wide end on the diaphragm-backing disc 56. To lock the spring 26 in its interposition between the base bottom 16 and diaphragm-backing disc S6 under all conditions, including operational yield of the diaphragm, the lower spring end is seated in a recess formed in this instance by arcuate rib formations 62 on the base bottom 16, and the upper spring end is in this instance turned inwardly into Ya hook 64 through which the screw 44 extends and which is interposed between the disc 56 and a washer 65. The diaphragm-backing disc 56 preferably extends close to the molded loop-like section 6d of the diaphragm, with an Outer Priphefal margin 68 of this disc being downwardly curved so as to keep the edge 70 thereat out of potentially damaging contact with the diaphragm 22 in all phases of its performance.

With the exemplary road marker of FIG. 2 installed in a road bed, the same will perform its described function of guiding drivers along the proper lane in daylight as well as in the dark. Assuming now that a wheel of a .vehicle passes over the marker, the wheel will impact the indicator 14 from one side and thereby force its diaphragm 22 .-to yield into the cup base, with the diaphragm undergoing its maximum yield deformation in a manner like or similar to that shown in FIG. 3 when the wheel passes over the top 70 of the indicator, whereupon the diaphragm and indicator thereon return on passage of the wheel to normal functioning disposition (FIG. 2). It will be noted from FIG. 3 that in the course of operational yield of the diaphragm 22 its loop-like section 60 is all-around forced into a reverse loop 72 which includes the normally nonlooped part of the diaphragm extending from the looped section 60 (FIG. 2) to the indicator 14, and this constitutes substantially the maximum deformation of the diaphragm in its operational yield. It also follows from FIGS. 2 and 3 that Ithe diaphragm 22 will in its yield action follow the path of least resistance by undergoing progressive, though exceedingly quick, flexure to its maximum deformation virtually without any resilient stretch. Return of the diaphragm to its normal functioning disposition is forceful and virtually instantaneous with the passage of the wheel and is largely caused by the spring 26 which in its diaphragm-return function is aided by the natural recovery properties of the elastic diaphragm itself, as will be readily understood.

Quick and unimpeded as is the described exure response of the diaphragm in its yield action under a passing wheel, its response in these respects is even enhanced by a snap-over action of the diaphragm. Thus, in the course of flexure of the diaphragm in its operational yield, its loop-like section 60 will all around pass through an S-like stage 74 (FIG. 4) from which it will snap over into the reverse loop 72 (FIG. 3), with this snap-over action of the diaphragm having on the yielding indicator 14 a snapaway effect from the passing wheel. This is of considerable advantage since in this fashion the diaphragms response to operational yielding in mere harmless flexure to the exclusion of any potentially harmful stretch or tensile stresses is carried particularly far. Moreover, and also important, in operational yield of the diaphragm under a passing wheel the diaphragm will, on and by virtue of its snap-over, emit a sound which is clearly heard by the offending driver and which is quite similar to the alarming sound of a suddenly deating and bumping tire and, hence, serves as an unmistakable warning to steer clear of these road markers.

As an additional feature of the present road marker, the loop-like section 60 of the diaphragm 22 is made of such extent that on operational yield of the diaphragm its deformation is such as to keep the volume of the sealed chamber 24 more or less constant at any instant, whereby the air in the sealed chamber 24, acting like an entrapped air mass in the brief interval of operational diaphragm yield, will not only not be compressed to any extent that might impede such diaphragm yield and induce appreciable momentary tensile stresses in the diaphragm, but will even assist the diaphragm into its progressive deformation by exure on operational yield and also on its quick recovery to normal functioning disposition with the passage of a wheel.

As already mentioned, the diaphragm-backing disc 56 is preferably and advantageously of considerable diameter and its outer peripheral margin 68 turned downwardly to its outer edge 70, whereby this disc also performs a safety function for the diaphragm mount of the lane indicator. Thus, on the rim of a wheel of a speeding vehicle over the marker and correspondingly more vigorous impact of the wheel with the lane indicator, the ensuing sharp yield of the diaphragm will, by clash of the edge of the backing disc with the base cup 12, be stopped safely before it could reach damaging proportions especially in momentary local stretch of the diaphragm material.

Engagement of the wider end of the conical spring 26 with the diaphragm-backing disc is also advantageous since the larger spring convolutions offer the least resistance to such momentary off-center displacement and canting of the disc and diaphragm as will occur on any operational yield of the latter, yet the spring Will under all conditions reliably perform its function of quick diaphragm return to normal disposition.

While the present road marker is thus in its reliable functioning particularly unaffected by thereover passing vehicle Wheels for the longest time, it is equally unaffected by even the heaviest and closely scraping snow-plowing blades on vehicles which necessarily must pass over the mar-ker to render the same functional again after a snow fall. It is in particular such snow-plowing blades which were severe on prior road markers and brought on early destruction of the latter, Whereas road markers of the present kind were tested extensively in this respect and safely withstood many passages of the fastest moving and heaviest snow-plowing blades, with the markers thus tested being of but slightly larger dimensions than shown in FIG. 2.

The invention may be carried out in other specific ways than those herein set forth without departing from the spirit and essential characteristics of the invention, and the present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, and all changes coming Within the meaning and equivalency range of the appended claims are intended to be embraced therein.

What is claimed is:

1. A road marker, comprising a base cup with a bottom and upright rim forming a chamber open at the top of the rim; a preformed resilient diaphragm peripherally anchored to said rim and extending across said rim to seal said chamber from the outside, said diaphragm having a central portion and a portion surrounding said central portion of which said surrounding portion is at least in part molded into a depression of substantial U-section and extending continuously around said central diaphragm portion; a traffic lane indicator on said central diaphragm portion and externally of said sealed chamber; and spring means in said sealed chamber on which said central diaphragm portion rests, with said indicator projecting above said rim top in normal 4diaphragm disposition.

2. A road marker as in claim 1, in which said indicator is a light reflector.

3. A road marker as in claim 1, which further comprises a rigid disc in said sealed chamber secured to said central diaphragm portion and with its outer margin extending close to said molded diaphragm depression, and said disc being seated on said spring means.

4. A road mar-ker as in claim 1, in which said molded diaphragm depression extends close to said rim.

References Citedl UNITED STATES PATENTS JACOB L. NACKENOFF, Primary Examiner. 

